Security, Upgrades & Backups

Security is one of the most important concerns that server administrators face. These guides will help you harden your system's security, addressing topics that include: configuring a firewall, creating and administering SSL certificates for transport layer security, offering secured SFTP user access to your Linode, and blocking malicious probes.

Securing Your Server

This is a starting point of best practices for hardening a production server. Topics include user accounts, an iptables firewall, SSH and disabling unused network services.

Linode Manager Security Controls

How to use two-factor authentication and other security controls in the Linode Manager.

Linux Security Basics

A collection of security practices to help you prevent common system exploits.

Recovering from a System Compromise

Steps to take if your Linode becomes compromised by unauthorized parties.

Use Public Key Authentication with SSH

Access your Linode via SSH using Public Key Authentication.

How to use a GPG key for SSH authentication

Generate a GPG key-pair, and convert it to an SSH key for authentication with your Linode.

Full Disk Encryption

Create a secure, LUKS-encrypted Debian Installation.

Install and Configure OSSEC on Debian 7

Install and configure OSSEC HIDS on Debian 7

Using Fail2ban to Secure Your Server

Use Fail2ban to block automated system attacks and further harden your server. Fail2ban monitors system logs for symptoms of an automated attack, bans the IP and alerts you of the attach through email.

Use One-Time Passwords for Two-Factor Authentication with SSH on Ubuntu 16.04 and Debian 8

Use Google Authenticator to enable two-factor authentication for SSH connections.

Use One-Time Passwords for Two-Factor Authentication with SSH on CentOS 7

Use OATH to enable two-factor authentication for SSH connections.